7ATOMIC RADII TRENDS WHY? INCREASES DOWN A FAMILY OR GROUPWHY?INCREASESAs you go down a family the n value increases making the radius larger.
8ATOMIC RADII TRENDS WHY? DECREASES ACROSS A PERIODWHY?As you go across a period the number of protons increases, (nuclear charge) pulling the electrons in tighter making the radius smaller.
9IONS - remember Metals Nonmetals Lose electrons becoming positive. Calcium – Ca[Ar]4s2Loses 4s2 e-s becomingCa+2 and [Ar] Noble gasConfiguration (Octet Rule)NonmetalsGain electrons becoming negative.Chlorine – Cl[Ne]3s23p5Gains one e- becoming Cl-1 and [Ar] Noble gas configuration.(Octet Rule)
10IONS – How can I remember? MetalsNonmetalsThis is Cat-ion - CATIONThis is Ann ion - ANIONHe is a “plussy” cat!She is unhappy and negative.
11IONIC RADII TRENDS WHY? INCREASES DOWN A FAMILY OR GROUPWHY?INCREASESAs you go down a family the n value increases making the radius larger.
12IONIC RADII TRENDSDECREASES then INCREASEACROSS A PERIODWHY?For the metals the nuclear charge is greater than then number of electrons pulling them in tighter making the radius smaller.At the nonmetals the radius gets larger because the ion has gained electrons.
14NONMETALLIC ATOM AND ION COMPARISON Why do the Noble Gases not have an ionic Radius?
15ATOM AND ION COMPARISON Why does Hydrogen not have an ionic Radius?
16Shielding EffectAs more electrons are added to atoms, the inner layers of electrons shield the outer electrons from the nucleus.The effective nuclear charge on those outer electrons is less, and so the outer electrons are less tightly held
18Ionization EnergyThe energy required to remove an electron from an atom is ionization energy. (measured in kilojoules, kJ)
19IONIZATION ENERGYThe larger the atom is, the easier its electrons are to remove.Ionization energy and atomic radius are inversely proportional.Ionization energy is always endothermic, that is energy is added to the atom to remove the electron.